If you mean that our physical body has anything or much to do with the next life..it does not in our view. The soul and it's spiritual nature is what survives and it is associated with the body in this life and serves as a vehicle of experience in this life..
After physical death the elements return from whence they came..
Baha'is believe however that since the body was a temporary host for the soul it should be treated with dignity and so we do not believe in cremation or embalming.. the body is washed and wrapped in silk or other valuable material and is placed in the casket..
For example, this elemental human body hath come forth from the mineral, the vegetable and the animal worlds, and after its death will be entirely changed into microscopic animal organisms; and according to the divine order and the driving forces of nature, these minute creatures will have an effect on the life of the universe, and will pass into other forms.
Now, if you consign this body to the flames, it will pass immediately into the mineral kingdom and will be kept back from its natural journey through the chain of all created things.
The elemental body, following death, and its release from its composite life, will be transformed into separate components and minuscule animals; and even though it will now be deprived of its composite life in human form, still the animal life is in it, and it is not entirely bereft of life. If, however, it be burned, it will turn into ashes and minerals, and once it has become mineral, it must inexorably journey onward to the vegetable kingdom, so that it may rise to the animal world. That is what is described as an overleap.
In short, the composition and decomposition, the gathering and scattering and journeying of all creatures must proceed according to the natural order, divine rule and the most great law of God, so that no marring nor impairment may affect the essential relationships which arise out of the inner realities of created things. This is why,according to the law of God, we are bidden to bury the dead.
(Abdu'l-Baha, Wisdom of Burying the Dead)